Many commercial applications today make use of aluminum flat bar. It is used to create items like truck frames, couplings, structural components, fishing reels and many other things. However, the process of making flat bar is more detailed than you might think and requires a great deal of precision. Here is information on how aluminum flat bar is created.
The Casting Process
Before flat bar can be made, one must first manufacture or purchase billets. A billet is used in the process of extrusion and it is created by casting molten aluminum in the shape of logs. The size and diameter is determined by the type of aluminum flat bar one wishes to make. In the manufacturing process, different alloys are added to create the type of aluminum needed. Some alloys are stronger than others and may be easier to work with. For instance, if 6061 aluminum is required, silicon and magnesium are added.
To create billets, molten aluminum passes through a filtration area to remove gases and impurities. Next it flows into the molds, forming aluminum logs. The logs may be thirty feet in length in some cases. Next, a machine cuts the logs into smaller sections.
Extruding Aluminum Flat Bar
In order to make the billet soft enough for the extrusion process it must be heated. Heating aluminum takes very high temperatures (as much as 1000 F). It’s important to heat the billet evenly and a special method is used. Without even heat, aluminum flat bar would not be possible.
Once the billet is properly heated it enters a press area. The billet is then pushed by a ram assembly through a special chamber containing a die. As the billet passes through the die, extruded aluminum flat bar is created. Depending on the size and shape of the die, many different extrusion products can be manufactured. This is known as direct extrusion.
After extruding, the flat bar is still hot so it is rapidly cooled in a quenching method.
Indirect or backward extrusion is a similar process but uses less energy. Instead of a billet pushed through a die (by solid a ram). The container holding the billet goes through a hollow ram to create the aluminum flat bar.
Once the process of extrusion is complete, the bar is stretched to eliminate warping and distortion. Next, the bar is cut to the desired lengths and then undergoes an aging process which can be open air or heated. Before shipment, the aluminum flat bar supplier checks to be sure the dimensions and sizes are accurate and of high quality.
